U.S. patent application number 15/469324 was filed with the patent office on 2017-09-28 for vascular flow diversion.
The applicant listed for this patent is Covidien LP. Invention is credited to Animesh Choubey, Ashok Nageswaran.
Application Number | 20170273810 15/469324 |
Document ID | / |
Family ID | 58545208 |
Filed Date | 2017-09-28 |
United States Patent
Application |
20170273810 |
Kind Code |
A1 |
Choubey; Animesh ; et
al. |
September 28, 2017 |
VASCULAR FLOW DIVERSION
Abstract
Devices that can be delivered into a vascular system to divert
flow are disclosed herein. According to some embodiments, devices
are provided for treating aneurysms by diverting flow. An
expandable device can comprise, for example, a plurality of
connector sections and a plurality of bridge sections. Each of the
connector sections may extend circumferentially about the
expandable device and include a plurality of connector struts. Each
of the plurality of bridge sections may be attached to and extend
between two of the connector sections and comprise a plurality of
parallel, non-branching, helical bridge members.
Inventors: |
Choubey; Animesh; (Chino,
CA) ; Nageswaran; Ashok; (Irvine, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Covidien LP |
Mansfield |
MA |
US |
|
|
Family ID: |
58545208 |
Appl. No.: |
15/469324 |
Filed: |
March 24, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62313055 |
Mar 24, 2016 |
|
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|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61F 2002/91583
20130101; A61F 2/885 20130101; A61F 2002/823 20130101; A61F
2002/91541 20130101; A61F 2250/0098 20130101; A61F 2002/825
20130101; A61F 2/915 20130101; A61F 2002/91525 20130101; A61F
2002/91558 20130101 |
International
Class: |
A61F 2/915 20060101
A61F002/915; A61F 2/88 20060101 A61F002/88 |
Claims
1. An expandable device comprising: a plurality of connector
sections, each of the connector sections extending
circumferentially about the expandable device and comprising a
plurality of connector struts; and a plurality of bridge sections,
each of the bridge sections attached to and extending between two
of the connector sections and comprising a plurality of parallel,
non-branching, helical bridge members.
2. The expandable device of claim 1, wherein a first one of the
bridge sections comprises first bridge members winding in a first
helical direction about an axis of the expandable device and a
second one of the bridge sections comprises second bridge members
winding in a second helical direction about the axis of the
expandable device, the first helical direction being opposite the
second helical direction.
3. The expandable device of claim 1, wherein each of the connector
struts is coupled to another connector strut at an apex.
4. The expandable device of claim 3, wherein each apex is coupled
to one of the bridge members.
5. The expandable device of claim 3, wherein some of the apices are
not coupled to any of the bridge members.
6. The expandable device of claim 3, wherein each bridge member is
coupled to a connector strut at a location other than the apex.
7. The expandable device of claim 1, wherein each bridge member is
coupled to a connector strut with a region of the bridge member
that is tangent to the connector strut.
8. The expandable device of claim 1, wherein at least a portion of
each of the connector struts of a connector section are parallel to
each other.
9. The expandable device of claim 1, wherein some of the bridge
members extend entirely through one of the connector sections
without being coupled to a connector strut of the one of the
connector sections.
10. The expandable device of claim 1, further comprising anchor
sections at longitudinal ends of the expandable device, each of the
anchor sections comprising a plurality of closed cells.
11. The expandable device of claim 1 wherein the expandable device
is a mesh.
12. The expandable device of claim 11 wherein the expandable device
is a laser cut sheet.
13. The expandable device of claim 11 wherein the mesh is
non-braided.
14. The expandable device of claim 1 wherein the device is
non-braided.
15. A device for treating an aneurysm, the device comprising: a
plurality of connector sections, each of the connector sections
extending circumferentially about the mesh structure and comprising
a plurality of connector struts; and a plurality of bridge
sections, each of the bridge sections attached to and extending
between two of the connector sections and comprising a plurality of
parallel, non-branching, helical bridge struts coupled to adjacent
connector struts, wherein the connector sections and bridge
sections together define a monolithic, self-expanding mesh
structure.
16. The device of claim 15, wherein a first one of the bridge
sections comprises first bridge struts winding in a first helical
direction about an axis of the mesh structure and a second one of
the bridge sections comprises second bridge struts winding in a
second helical direction about the axis of the mesh structure, the
first helical direction being opposite the second helical
direction.
17. The device of claim 15, wherein each of the connector struts is
coupled to another connector strut at an apex.
18. The device of claim 17, wherein each apex is coupled to one of
the bridge struts.
19. The device of claim 17, wherein some of the apices are not
coupled to any of the bridge struts.
20. The device of claim 17, wherein each bridge strut is coupled to
a connector strut at a location other than the apex.
21. The device of claim 15, wherein each bridge strut is coupled to
a connector strut with a region of the bridge strut that is tangent
to the connector strut.
22. The device of claim 15, wherein at least a portion of each of
the connector struts of a connector section are parallel to each
other.
23. The device of claim 15, wherein some of the bridge struts
extend entirely through one of the connector sections without being
coupled to a connector strut of the one of the connector
sections.
24. The device of claim 15, further comprising anchor sections at
longitudinal ends of the expandable device, each of the anchor
sections comprising a plurality of closed cells.
25. The device of claim 15 wherein the mesh is a laser cut
sheet.
26. The device of claim 15 wherein the mesh is non-braided.
27. The device of claim 15 wherein the mesh is made of one or more
superelastic materials.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims the benefit of and priority
to U.S. Provisional Patent Application No. 62/313,055, filed Mar.
24, 2016, which is incorporated herein by reference in its
entirety.
TECHNICAL FIELD
[0002] The subject technology relates generally to methods and
devices for diverting blood flow in a blood vessel, and
particularly to inhibiting blood flow into an aneurysm. Some
embodiments of the subject technology relate to flow-diverting
devices including a plurality of interconnected struts.
BACKGROUND
[0003] Aneurysms are an abnormal bulging or ballooning of a blood
vessel that can result from the vessel wall being weakened by
disease, injury, or a congenital abnormality. Aneurysms have thin,
weak walls and have a tendency to rupture, which can lead to
stroke, death, disability, etc. One method of treating aneurysms
includes inserting a flow-diverting stent or braid into a parent
vessel that includes the aneurysm to be treated. Such stents or
braids can be inserted into a vessel in a collapsed state,
positioned next to the neck of the aneurysm, and expanded into
apposition with the vessel wall. If the stent or braid has a
sufficiently low porosity, it can function to block the flow of
blood through the device and into the aneurysm to induce
embolization of the aneurysm.
[0004] However, some aneurysms--and especially cerebral
aneurysms--are located in small and tortuous portions of the
vasculature. Current designs for flow-diverting stents or braids
have difficulty achieving a snug fit across the neck of the
aneurysm if the parent vessel is curved, twisted, or forked. For
example, current designs generally suffer from crimping or kinking
when positioned in such tortuous vessels. This can make it more
difficult to position a flow-diverting device and can cause the
device to have an inadequate porosity as the device is expanded
within the vessel. Also, current designs often undesirably block
blood flow to branching or secondary vessels that are close to the
aneurysm. Accordingly, there exists a need for improved
flow-diverting devices for treating aneurysms.
SUMMARY
[0005] Expandable devices can be delivered into vascular system to
divert flow. According to some embodiments, expandable devices are
provided for treating aneurysms by diverting flow. A flow-diverting
expandable device can comprise a plurality of struts and/or bridges
and configured to be implanted in a blood vessel. The expandable
device can be expandable to an expanded state at an aneurysm. The
expandable device can have at least a section for spanning the neck
of the aneurysm and a plurality of pores or openings located
between the struts/bridges. The expandable device can have a
sidewall and a plurality of pores/openings in the sidewall that are
sized to inhibit flow of blood through the sidewall into an
aneurysm to a degree sufficient to lead to thrombosis and healing
of the aneurysm when the expandable device is positioned in a blood
vessel and adjacent to the aneurysm. The subject technology is
illustrated, for example, according to various aspects described
below.
[0006] Further, some embodiments can provide a delivery system for
treating an aneurysm. The system can comprise a microcatheter
configured to be implanted into a blood vessel, a core member,
extending within the microcatheter, having a distal segment, and
the device extending along the core member distal segment.
[0007] The subject technology is illustrated, for example,
according to various aspects described below. Various examples of
aspects of the subject technology are described as numbered clauses
(1, 2, 3, etc.) for convenience. These are provided as examples and
do not limit the subject technology.
[0008] Clause 1. An expandable device comprising: [0009] a
plurality of connector sections, each of the connector sections
extending circumferentially about the expandable device and
comprising a plurality of connector struts; and [0010] a plurality
of bridge sections, each of the bridge sections attached to and
extending between two of the connector sections and comprising a
plurality of parallel, non-branching, helical bridge members.
[0011] Clause 2. The expandable device of clause 1, wherein a first
one of the bridge sections comprises first bridge members winding
in a first helical direction about an axis of the expandable device
and a second one of the bridge sections comprises second bridge
members winding in a second helical direction about the axis of the
expandable device, the first helical direction being opposite the
second helical direction.
[0012] Clause 3. The expandable device of clause 1, wherein each of
the connector struts is coupled to another connector strut at an
apex.
[0013] Clause 4. The expandable device of clause 3, wherein each
apex is coupled to one of the bridge members.
[0014] Clause 5. The expandable device of clause 3, wherein some of
the apices are not coupled to any of the bridge members.
[0015] Clause 6. The expandable device of clause 3, wherein each
bridge member is coupled to a connector strut at a location other
than the apex.
[0016] Clause 7. The expandable device of clause 1, wherein each
bridge member is coupled to a connector strut with a region of the
bridge member that is tangent to the connector strut.
[0017] Clause 8. The expandable device of clause 1, wherein at
least a portion of each of the connector struts of a connector
section are parallel to each other.
[0018] Clause 9. The expandable device of clause 1, wherein some of
the bridge members extend entirely through one of the connector
sections without being coupled to a connector strut of the one of
the connector sections.
[0019] Clause 10. The expandable device of clause 1, further
comprising anchor sections at longitudinal ends of the expandable
device, each of the anchor sections comprising a plurality of
closed cells.
[0020] Clause 11. The expandable device of clause 1 wherein the
expandable device is a mesh.
[0021] Clause 12. The expandable device of clause 11 wherein the
expandable device is a laser cut sheet.
[0022] Clause 13. The expandable device of clause 11 wherein the
mesh is non-braided.
[0023] Clause 14. The expandable device of clause 1 wherein the
device is non-braided.
[0024] Clause 15. A device for treating an aneurysm, the device
comprising: [0025] a plurality of connector sections, each of the
connector sections extending circumferentially about the mesh
structure and comprising a plurality of connector struts; and
[0026] a plurality of bridge sections, each of the bridge sections
attached to and extending between two of the connector sections and
comprising a plurality of parallel, non-branching, helical bridge
struts coupled to adjacent connector struts, [0027] wherein the
connector sections and bridge sections together define a
monolithic, self-expanding mesh structure.
[0028] Clause 16. The device of clause 15, wherein a first one of
the bridge sections comprises first bridge struts winding in a
first helical direction about an axis of the mesh structure and a
second one of the bridge sections comprises second bridge struts
winding in a second helical direction about the axis of the mesh
structure, the first helical direction being opposite the second
helical direction.
[0029] Clause 17. The device of clause 15, wherein each of the
connector struts is coupled to another connector strut at an
apex.
[0030] Clause 18. The device of clause 17, wherein each apex is
coupled to one of the bridge struts.
[0031] Clause 19. The device of clause 17, wherein some of the
apices are not coupled to any of the bridge struts.
[0032] Clause 20. The device of clause 17, wherein each bridge
strut is coupled to a connector strut at a location other than the
apex.
[0033] Clause 21. The device of clause 15, wherein each bridge
strut is coupled to a connector strut with a region of the bridge
strut that is tangent to the connector strut.
[0034] Clause 22. The device of clause 15, wherein at least a
portion of each of the connector struts of a connector section are
parallel to each other.
[0035] Clause 23. The device of clause 15, wherein some of the
bridge struts extend entirely through one of the connector sections
without being coupled to a connector strut of the one of the
connector sections.
[0036] Clause 24. The device of clause 15, further comprising
anchor sections at longitudinal ends of the expandable device, each
of the anchor sections comprising a plurality of closed cells.
[0037] Clause 25. The device of clause 15 wherein the mesh
structure is a laser cut sheet.
[0038] Clause 26. The device of clause 15 wherein the mesh
structure is non-braided.
[0039] Clause 27. The device of clause 15 wherein the mesh
structure is made of a superelastic material.
[0040] Additional features and advantages of the subject technology
will be set forth in the description below, and in part will be
apparent from the description, or may be learned by practice of the
subject technology. The advantages of the subject technology will
be realized and attained by the structure particularly pointed out
in the written description and clauses hereof as well as the
appended drawings.
[0041] It is to be understood that both the foregoing general
description and the following detailed description are exemplary
and explanatory and are intended to provide further explanation of
the subject technology.
BRIEF DESCRIPTION OF THE DRAWINGS
[0042] The accompanying drawings, which are included to provide
further understanding of the subject technology and are
incorporated in and constitute a part of this description,
illustrate aspects of the subject technology and, together with the
specification, serve to explain principles of the subject
technology.
[0043] FIG. 1A shows a plan view of an expandable device with a
strut pattern, according to some embodiments of the subject
technology.
[0044] FIG. 1B shows an enlarged plan view of a portion of the
expandable device of FIG. 1A, according to some embodiments of the
subject technology.
[0045] FIG. 2A shows a perspective view of struts, according to
some embodiments of the subject technology.
[0046] FIG. 2B shows a cross-sectional view of a strut, according
to some embodiments of the subject technology.
[0047] FIG. 3A shows a plan view of an expandable device with a
strut pattern, according to some embodiments of the subject
technology.
[0048] FIG. 3B shows an enlarged plan view of a portion of the
expandable device of FIG. 3A, according to some embodiments of the
subject technology.
[0049] FIG. 4A shows a plan view of an expandable device with a
strut pattern, according to some embodiments of the subject
technology.
[0050] FIG. 4B shows an enlarged plan view of a portion of the
expandable device of FIG. 4A, according to some embodiments of the
subject technology.
[0051] FIG. 5A shows a plan view of an expandable device with a
strut pattern, according to some embodiments of the subject
technology.
[0052] FIG. 5B shows an enlarged plan view of a portion of the
expandable device of FIG. 5A, according to some embodiments of the
subject technology.
[0053] FIG. 6A shows a plan view of an expandable device with a
strut pattern, according to some embodiments of the subject
technology.
[0054] FIG. 6B shows an enlarged plan view of a portion of the
expandable device of FIG. 6A, according to some embodiments of the
subject technology.
[0055] FIG. 7A shows a plan view of an expandable device with a
strut pattern, according to some embodiments of the subject
technology.
[0056] FIG. 7B shows an enlarged plan view of a portion of the
expandable device of FIG. 7A, according to some embodiments of the
subject technology.
[0057] FIG. 8A shows a plan view of an expandable device with a
strut pattern, according to some embodiments of the subject
technology.
[0058] FIG. 8B shows an enlarged plan view of a portion of the
expandable device of FIG. 8A, according to some embodiments of the
subject technology.
[0059] FIG. 9A shows a plan view of an expandable device with a
strut pattern, according to some embodiments of the subject
technology.
[0060] FIG. 9B shows an enlarged plan view of a portion of the
expandable device of FIG. 9A, according to some embodiments of the
subject technology.
[0061] FIG. 10A shows a plan view of an expandable device with a
strut pattern, according to some embodiments of the subject
technology.
[0062] FIG. 10B shows an enlarged plan view of a portion of the
expandable device of FIG. 10A, according to some embodiments of the
subject technology.
[0063] FIG. 11A shows a plan view of an expandable device with a
strut pattern, according to some embodiments of the subject
technology.
[0064] FIG. 11B shows an enlarged plan view of a portion of the
expandable device of FIG. 11A, according to some embodiments of the
subject technology.
[0065] FIG. 12A shows a plan view of an expandable device with a
strut pattern, according to some embodiments of the subject
technology.
[0066] FIG. 12B shows an enlarged plan view of a portion of the
expandable device of FIG. 12A, according to some embodiments of the
subject technology.
[0067] FIG. 13A shows a plan view of an expandable device with a
strut pattern, according to some embodiments of the subject
technology.
[0068] FIG. 13B shows an enlarged plan view of a portion of the
expandable device of FIG. 13A, according to some embodiments of the
subject technology.
[0069] FIG. 14A shows a plan view of an expandable device with a
strut pattern, according to some embodiments of the subject
technology.
[0070] FIG. 14B shows an enlarged plan view of a portion of the
expandable device of FIG. 14A, according to some embodiments of the
subject technology.
[0071] FIGS. 15A-15D shows a side view of an expandable device in
various curved states of different curvatures, according to some
embodiments of the subject technology.
DETAILED DESCRIPTION
[0072] In the following detailed description, specific details are
set forth to provide an understanding of the subject technology.
However, the subject technology may be practiced without some of
these specific details. In some instances, well-known structures
and techniques have not been shown in detail so as not to obscure
the subject technology.
[0073] An expandable device comprising a thin film forming a mesh
can be used to treat an aneurysm. The expandable device can impede
blood flow along an aneurysmal flow path between the prevailing
direction of arterial flow and the interior of the aneurysm via,
e.g., high pore density, small pore size and/or high material
coverage across the aneurysmal flow path, and facilitate
endothelial growth across the neck of the aneurysm or otherwise
across the aneurysmal flow path. The expandable device can comprise
a single component, low profile, high pore density flow diverter of
a single material and/or of monolithic construction. The expandable
device can facilitate accurate placement by requiring less
foreshortening as compared to other commercially available devices,
including braided devices. The expandable device can have a
thickness that is small enough to enable placement in smaller blood
vessels, thereby opening new areas of treatment for flow
diversion.
[0074] According to some embodiments, an expandable device, such as
a stent, can have a flow diverting section or other portion of the
device that provides embolic properties so as to interfere with
blood flow in (or into) the body space (e.g., an aneurysm) in (or
across) which the device is deployed. The sidewall material
coverage, porosity, and/or pore size of one or more sections of the
device can be selected to interfere with blood flow to a degree
sufficient to lead to thrombosis of the aneurysm or other body
space.
[0075] According to some embodiments, the expandable device can be
configured to interfere with blood flow to generally reduce the
exchange of blood between the parent vessel and an aneurysm, which
can induce thrombosis of the aneurysm. A device (or a device
component, such as a sidewall of a stent or a section of such a
sidewall) that interferes with blood flow can be said to have a
"flow diverting" property.
[0076] According to some embodiments, a porosity of the expandable
device is equal to a ratio of an open surf ace area of the
expandable device to a total surface area of the expandable device.
The expandable device may comprise a plurality of struts, which
form pores or cells as open areas between the struts.
[0077] The device can exhibit a porosity configured to reduce
haemodynamic flow into and/or induce thrombosis within an aneurysm.
The device can simultaneously allow perfusion to an adjacent branch
vessel whose ostium is crossed by a portion of the device. The
device can exhibit a high degree of flexibility due to the
materials used, the density (i.e., the porosity) of the struts, and
the arrangement of struts.
[0078] The device can be self-expanding to a relaxed state or an
expanded state. As used herein, the relaxed state is one to which
the expandable device will self-expand in the absence of any
containment or external forces. As used herein, expanded state is
one to which the expandable device is capable of self-expanding,
ignoring any containment, such by as a blood vessel. For example
and simplicity of measurement, this expanded state can be one to
which the expandable device will self-expand within a straight,
non-tapering cylindrical tube with an inside diameter that is
slightly smaller than the maximum diameter of the expandable device
in the relaxed state.
[0079] The struts and bridge configuration of the expandable device
may be formed, for example, by laser cutting a pre-formed tube or
sheet, by interconnecting components (e.g., by laser welding), by
vapor deposition techniques, or combinations thereof. A more
detailed description of methods by which an expandable device may
be formed is provided further herein.
[0080] According to some embodiments, the expandable device may
include a plurality of individual struts and individual cells, as
well as a first longitudinal edge and a second longitudinal edge.
The first longitudinal edge and the second longitudinal edge may be
connected to each other to form a substantially cylindrical shape
or a circumferentially continuous cylindrical shape by welding,
soldering, or otherwise joining the struts or edges.
[0081] According to some embodiments in which the device is not a
circumferentially continuous cylinder, the first edge and second
edge may be formed, for example, by cutting a preformed, etched or
laser-cut tube longitudinally along the length of the tube.
Regardless of the manner of forming, the expandable device may be
rolled or curled such that the first and second longitudinal edges
overlap one another when the expandable device is in a compressed
state and/or an expanded state. Upon release from a constraint
(e.g. upon exiting a catheter), the expandable device (when
configured to be self-expanding) may spring open and attempt to
assume an expanded state.
[0082] While the views provided in several of the figures (e.g.,
FIGS. 1A, 1B, 3A-8A, 9A, and 10A-14B) show expandable devices laid
flat for ease of explanation and understanding, it will be
understood that the devices can possess a tubular shape (e.g.,
FIGS. 8B, 9B and 15A-15D), and the laid-flat drawings presented
herein depict the configuration of a sidewall of the tube. While in
the tubular shape, the expandable devices can have open ends of a
lumen extending through the expandable device.
[0083] Many embodiments of the subject technology are directed to
expandable, flow-diverting mesh devices formed of a non-braided,
thin-film mesh structure that includes a plurality of helical
bridge struts (described in greater detail below). The mesh devices
of the subject technology provide several advantages over
conventional, braided flow-diverting devices, especially braided
devices. For example, because the mesh devices disclosed herein are
non-braided, they foreshorten significantly less than braided
devices and thus may be more accurately deployed and positioned
within the parent vessel. Moreover, many of the mesh devices
disclosed herein are formed of a monolithic piece of metal and thus
may have a very small wall thickness (e.g., about 15-20 microns),
thereby enabling placement in smaller blood vessels and allowing
new anatomical areas of treatment for flow diversion. Finally,
because of the density, shape and arrangement of struts, the mesh
devices of the subject technology are more flexible than
conventional stents and may be positioned around tight corners or
bends without kinking.
[0084] According to some embodiments, for example as shown in FIGS.
1A and 1B, an expandable device 100 can comprise a plurality of
connector struts 120 within a plurality of connector sections 110
and a plurality of bridge members 160 within a plurality of bridge
sections 150. Some or all of the bridge sections 150 can be
disposed longitudinally between a pair of connector sections 110.
Some or all of the connector sections 110 and the bridge sections
150 can extend along some or all of a circumference of the
expandable device 100 when the expandable device 100 forms a
tubular shape. Some or all of the connector sections 110 can be
connected to bridge sections 150 on opposing longitudinal sides of
the connector section 110. Some or all of the bridge sections 150
can be connected to connector sections 110 on opposing longitudinal
sides of the bridge section 150.
[0085] According to some embodiments, for example as shown in FIG.
1B, the connector struts 120 of the connector section 110 can be
connected to each other within the connector section 110. As
depicted, the connector struts 120 can be arranged in a "zigzag"
pattern and the connector section 110 formed thereby can be in the
form of a circumferential band, or a V-strut band. An end of one
connector strut 120 can be connected to an end of another connector
strut 120. One or more connector struts 120 can be connected at an
apex 130. Some or all of the apices 130 can be formed at
longitudinal ends of the connector section 110, such that each of
the apices 130 faces an adjoining bridge section 150. Each
connector section 110 can have 28-108 connector struts 120.
[0086] According to some embodiments, for example as shown in FIG.
1B, the bridge members 160 of the bridge section 150 can be
connected to connector struts 120 of adjacent connector sections
110. Each of the bridge members 160 can connect to a connector
strut 120 (e.g., at an apex 130) of one connector section 110 with
one end of the bridge member 160 and to a connector strut 120
(e.g., at an apex 130) of another connector section 110 with an
opposite end of the bridge member 160. Between the ends of the
bridge member 160, the bridge member 160 can be non-branching.
Between the ends of the bridge member 160, the bridge member 160
can be unconnected to any other bridge member 160. Each bridge
section 150 can have, e.g., 28-108 bridge members 160. Each bridge
member 160 can span a circumferential distance of the expandable
device 100 while the expandable device 100 is in a tubular shape.
For example, each bridge member 160 can span 30.degree. to
180.degree. about the longitudinal axis, for example 120.degree..
By further example, each bridge member 160 can span a distance of 3
to 54 apices 130 between terminal ends of the bridge member 160. At
least a portion of a bridge member 160 can be parallel to some or
all of the other bridge members 160 of the same bridge section 150
when the expandable device 100 is represented in a laid-flat view
such as in FIGS. 1A-1B, etc. At least a portion of a bridge member
160 in a helical shape can be parallel to some or all of the other
bridge members 160 in a helical shape of the same bridge section
150 when the expandable device 100 is considered in its tubular
form. As used herein, two helical shapes are considered "parallel"
if they wind about the same axis, at the same distance (i.e.,
radius) from the axis, with the same pitch angle or helix angle
with respect to the axis, and in the same rotational direction
(dextrorotatory or levorotatory) with respect to the axis.
[0087] According to some embodiments, a helical winding direction
of the bridge members 160 of one bridge section 150 can be
different than a helical winding direction of the bridge members
160 of a different bridge section 150. For example, the helical
winding direction of some bridge members 160 of one bridge section
150 can be dextrorotatory and the helical winding direction of the
bridge members 160 of a different bridge section 150 can be
levorotatory. The helical winding direction within any given bridge
section 150 can be different than the helical winding direction of
any adjacent bridge section 150. For example, alternating bridge
sections 150 along a longitudinal length of the expandable device
100 can have alternating helical winding directions relative to
each other. When the expandable device 100 is extended
longitudinally, the bridge members 160 of the bridge sections 150
can straighten relative to the longitudinal axis, causing the
connector sections 110 to rotate about the axis in different
directions. This allows the extreme ends of the expandable device
100 to rotate relative to each other less than they would if the
bridge members 160 of every bridge section 150 were wound in the
same helical direction, or not at all.
[0088] According to some embodiments, a bridge gap 162 is a
distance between a pair of adjacent bridge members 160. The bridge
gap 162 can be measured across parallel portions of pairs of
adjacent bridge members 160. The bridge gap 162 can be the same
(e.g., uniform) or different among different pairs of bridge
members 160 within a single bridge section 150. The bridge gap 162
can be the same/uniform or different among different bridge
sections 150 of a single device 100. The bridge gap 162 can be 1 to
250 .mu.m, for example greater than 100 .mu.m.
[0089] According to some embodiments, the bridge members 160 form a
pitch angle 164 with respect to a line that is orthogonal to the
longitudinal axis of the expandable device 100. The pitch angle 164
can be the same/uniform or different for different bridge members
160 within a single bridge section 150. The pitch angle 164 can be
the same/uniform or different among different bridge sections 150
of a single device 100. The pitch angle 164 can be 10.degree. to
60.degree., for example 19.degree..
[0090] According to some embodiments, an apex gap 132 is a distance
between a pair of adjacent apices 130 on a same longitudinal side
of a connector section 110. The apex gap 132 can be measured as
orthogonal to a longitudinal axis of the expandable device 100. The
apex gap 132 can be the same/uniform or different among different
pairs of apices 130 within a single connector section 110. The apex
gap 132 can be the same/uniform or different among different
connector sections 110 of a single device 100. The apex gap 132 can
be 10 to 450 .mu.m, for example 300 .mu.m.
[0091] According to some embodiments, a connector section length
112 is a longitudinal distance between opposing longitudinal sides
of a connector section 110 (e.g., between a pair of bridge sections
150). The connector section length 112 can be measured as parallel
to a longitudinal axis of the expandable device 100. The connector
section length 112 can be the same/uniform or different among
different connector sections 110 of a single device 100. The
connector section length 112 can be 10 to 450 .mu.m, for example
300 .mu.m.
[0092] According to some embodiments, a bridge section length 152
is a longitudinal distance between opposing longitudinal sides of a
bridge section 150 (e.g., between a pair of connector sections
110). The bridge section length 152 can be measured as parallel to
a longitudinal axis of the expandable device 100. The bridge
section length 152 can be the same/uniform or different among
different bridge sections 150 of a single device 100. The bridge
section length 152 can be 500 to 4500 .mu.m, for example 1,100
.mu.m.
[0093] According to some embodiments, some or all of the bridge
members 160 and/or some or all of the connector struts 120 can
comprise a radiopaque marker. The radiopaque marker can be disposed
on a substantially straight section of a bridge member 160 and/or a
connector strut 120, so the radiopaque marker is predominantly not
subject to bending or flexing. For example, the radiopaque
marker(s) can be disposed a distance away from an apex 130. The
radiopaque marker(s) can be formed on the bridge members 160 and/or
the connector struts 120 by a process that is the same or different
than a process used to form the bridge members 160 and/or the
connector struts 120, which are discussed further herein.
[0094] According to some embodiments, the expandable device 100 can
provide a porosity that is the range of 5%-95%. The cells of the
expandable device 100 can provide a pore size that is between 5 and
450 .mu.m. A pore size can be measured via a maximum inscribed
circle technique.
[0095] FIG. 2A depicts a perspective view of a connector strut 120
according to some embodiments of the subject technology. FIG. 2B
depicts a cross-sectional view of the connector strut 120 according
to one aspect of the subject technology. As shown, the connector
strut 120 has a length, a width, and a thickness. The thickness can
be measured as a dimension that is orthogonal to a central axis
when the expandable device 100 is considered in a tubular shape or
as a dimension that is orthogonal to a plane of the expandable
device 100 when represented as laid-flat. The length can be
measured as a distance extending between ends of a strut, where the
ends connect to another structure. The width can be measured as the
distance that is generally orthogonal to the length and thickness.
The width and length of a strut can contribute to a surface
coverage and porosity of the expandable device 100. According to
some embodiments, the connector strut 120 can have a square
cross-section. According to some embodiments, the bridge member 160
can have a similar square cross-section. However, the connector
strut 120 and/or the bridge member 160 may have other suitable
cross-sectional shapes, such as rectangular, polygonal, round,
ovoid, elliptical, or combinations thereof.
[0096] According to some embodiments, a thickness of the connector
struts 120 and/or the bridge members 160 can be 5 to 50 .mu.m, for
example 50 .mu.m. According to some embodiments, a width of the
connector struts 120 and/or the bridge members 160 can be 5 to 50
.mu.m, for example 50 .mu.m.
[0097] According to some embodiments, for example as shown in FIGS.
3A and 3B, an expandable device can have a number of apices that is
greater than a number of bridge members, such that at least some of
the apices do not connect directly to a bridge member.
[0098] According to some embodiments, for example as shown in FIGS.
3A and 3B, an expandable device 300 can comprise a plurality of
connector struts 320 and apices 330 within a plurality of connector
sections 310 and a plurality of bridge members 360 within a
plurality of bridge sections 350. Features of the expandable device
300 that are identified with reference numerals that differ from
the reference numerals for the expandable device 100 by a multiple
of 100 can have the same aspects as the corresponding features in
the expandable device 100, unless noted otherwise.
[0099] According to some embodiments, for example as shown in FIGS.
3A and 3B, at least some of the apices 330 do not connect directly
to a bridge member 360. For example, a number of apices 330 or
connector struts 320 can be greater than a number of bridge members
360. Accordingly, at least some of the connector struts 320
terminate at an apex 330 that does not connect to a bridge member
360. For example, a given connector section 310 can form a number
of apices 330 that face an adjacent bridge section 350, and the
bridge section 350 can comprise fewer (for example, one-half or
one-third) bridges than such adjacent, facing apices. Accordingly,
every other (or every third, fourth, fifth, etc.) adjacent, facing
apex 330 can be connected to a bridge of the adjacent bridge
section 350, and the remaining apices can be unconnected to a
bridge.
[0100] According to some embodiments, for example as shown in FIGS.
4A and 4B, an expandable device 400 can comprise a plurality of
connector struts 420 and apices 430 within a plurality of connector
sections 410 and a plurality of bridge members 460 within a
plurality of bridge sections 450. Features of the expandable device
400 that are identified with reference numerals that differ from
the reference numerals for the expandable device 100 by a multiple
of 100 can have the same aspects as the corresponding features in
the expandable device 100, unless noted otherwise.
[0101] According to some embodiments, for example as shown in FIGS.
4A and 4B, at least some of the apices 430 do not connect directly
to a bridge member 460. For example, a number of apices 430 or
connector struts 420 can be greater than a number of bridge members
460. Accordingly, at least some of the connector struts 420
terminate at an apex 430 that does not connect to a bridge member
460. For example, a given connector section 410 can form a number
of apices 430 that face an adjacent bridge section 450, and the
bridge section 450 can comprise fewer (for example, one-half or
one-third) bridges than such adjacent, facing apices. Accordingly,
every other (or every third, fourth, fifth, etc.) adjacent, facing
apex 430 can be connected to a bridge of the adjacent bridge
section 450, and the remaining apices can be unconnected to a
bridge.
[0102] According to some embodiments, for example as shown in FIGS.
5A and 5B, bridge members of an expandable device can connect to
connector struts at a location other than at an apex where two
connector struts are coupled together.
[0103] According to some embodiments, for example as shown in FIGS.
5A and 5B, an expandable device 500 can comprise a plurality of
connector struts 520 and apices 530 within a plurality of connector
sections 510 and a plurality of bridge members 560 within a
plurality of bridge sections 550. Features of the expandable device
500 that are identified with reference numerals that differ from
the reference numerals for the expandable device 100 by a multiple
of 100 can have the same aspects as the corresponding features in
the expandable device 100, unless noted otherwise.
[0104] According to some embodiments, for example as shown in FIGS.
5A and 5B, some or all of the bridge members 560 connect to a
connector section 510 at a location that is not, or is slightly
offset from a centerline of, an apex 530 of two connector struts
520. Instead, some or all of the bridge members 560 connect more
closely to one connector strut 520 than to the other connector
strut 520 with which it forms an apex 530. In this configuration,
the connection to the bridge member 560 is less likely to interfere
with the flexing of the apex 530.
[0105] According to some embodiments, for example as shown in FIGS.
6A and 6B, each and every bridge member of an expandable device can
extend in the same helical winding direction.
[0106] According to some embodiments, for example as shown in FIGS.
6A and 6B, an expandable device 600 can comprise a plurality of
connector struts 620 and apices 630 within a plurality of connector
sections 610 and a plurality of bridge members 660 within a
plurality of bridge sections 650. Features of the expandable device
600 that are identified with reference numerals that differ from
the reference numerals for the expandable device 100 by a multiple
of 100 can have the same aspects as the corresponding features in
the expandable device 100, unless noted otherwise.
[0107] According to some embodiments, for example as shown in FIGS.
6A and 6B, a helical winding direction of the bridge members 660 of
one bridge section 650 can be the same as a helical winding
direction of the bridge members 660 of a different bridge section
650. For example, the helical winding direction of all bridge
members 660 of all bridge sections 650 can be dextrorotatory or
levorotatory. When the expandable device 600 is extended
longitudinally, the bridge members 660 of the bridge sections 650
can straighten relative to the longitudinal axis, causing the
connector sections 610 to rotate about the axis in the same
direction. This allows the extreme ends of the expandable device
600 to rotate relative to each other in the same way throughout the
expansion of the expandable device 600.
[0108] According to some embodiments, for example as shown in FIGS.
7 A and 7B, an expandable device can incorporate (1) the connection
of struts as described with respect to the expandable device 500
and (2) the helical winding direction as described with respect to
the expandable device 600.
[0109] According to some embodiments, for example as shown in FIGS.
7 A and 7B, an expandable device 700 can comprise a plurality of
connector struts 720 and apices 730 within a plurality of connector
sections 710 and a plurality of bridge members 760 within a
plurality of bridge sections 750. Features of the expandable device
700 that are identified with reference numerals that differ from
the reference numerals for the expandable device 100 by a multiple
of 100 can have the same aspects as the corresponding features in
the expandable device 100, unless noted otherwise.
[0110] According to some embodiments, for example as shown in FIGS.
7 A and 7B, a helical winding direction of the bridge members 760
of one bridge section 750 can be the same as a helical winding
direction of the bridge members 760 of a different bridge section
750. According to some embodiments, some or all of the bridge
members 760 connect to a connector section 710 at a location that
is not at, or is slightly offset from, a centerline of an apex 730
of two connector struts 720. Instead, some or all of the bridge
members 760 connect more closely to one connector strut 720 than to
the other connector strut 720 with which it forms an apex 730.
According to some embodiments, at least some of the apices 730 do
not connect directly to a bridge member 760.
[0111] According to some embodiments, for example as shown in FIGS.
8A and 8B, an expandable device can incorporate (1) the unconnected
apices described with respect to the expandable device 300 and (2)
the connection of struts as described with respect to the
expandable device 500.
[0112] According to some embodiments, for example as shown in FIGS.
8A and 8B, an expandable device 800 can comprise a plurality of
connector struts 820 and apices 830 within a plurality of connector
sections 810 and a plurality of bridge members 860 within a
plurality of bridge sections 850. Features of the expandable device
800 that are identified with reference numerals that differ from
the reference numerals for the expandable device 100 by a multiple
of 100 can have the same aspects as the corresponding features in
the expandable device 100, unless noted otherwise.
[0113] According to some embodiments, for example as shown in FIGS.
8A and 8B, a helical winding direction of the bridge members 860 of
one bridge section 850 can be different than a helical winding
direction of the bridge members 860 of a different bridge section
850. According to some embodiments, some or all of the bridge
members 860 connect to a connector section 810 at a location that
is not at, or is slightly offset from, a centerline of an apex 830
of two connector struts 820. Instead, some or all of the bridge
members 860 connect more closely to one connector strut 820 than to
the other connector strut 820 with which it forms an apex 830.
According to some embodiments, at least some of the apices 830 do
not connect directly to a bridge member 860.
[0114] According to some embodiments, for example as shown in FIGS.
9A and 9B, an expandable device can incorporate (1) the unconnected
apices described with respect to the expandable device 300, (2) the
connection of struts as described with respect to the expandable
device 500, and (3) the helical winding direction as described with
respect to the expandable device 600.
[0115] According to some embodiments, for example as shown in FIGS.
9A and 9B, an expandable device 900 can comprise a plurality of
connector struts 920 and apices 930 within a plurality of connector
sections 910 and a plurality of bridge members 960 within a
plurality of bridge sections 950. Features of the expandable device
900 that are identified with reference numerals that differ from
the reference numerals for the expandable device 100 by a multiple
of 100 can have the same aspects as the corresponding features in
the expandable device 100, unless noted otherwise.
[0116] According to some embodiments, for example as shown in FIGS.
9A and 9B, a helical winding direction of the bridge members 960 of
one bridge section 950 can be the same a helical winding direction
of the bridge members 960 of a different bridge section 950.
According to some embodiments, some or all of the bridge members
960 connect to a connector section 910 at a location that is not
at, or is slightly offset from, a centerline of an apex 930 of two
connector struts 920. Instead, some or all of the bridge members
960 connect more closely to one connector strut 920 than to the
other connector strut 920 with which it forms an apex 930.
According to some embodiments, at least some of the apices 930 do
not connect directly to a bridge member 960.
[0117] According to some embodiments, for example as shown in FIGS.
10A and 10B, an expandable device can incorporate (1) the
connection of struts as described with respect to the expandable
device 500 and (2) the helical winding direction as described with
respect to the expandable device 600.
[0118] According to some embodiments, for example as shown in FIGS.
10A and 10B, an expandable device 1000 can comprise a plurality of
connector struts 1020 and apices 1030 within a plurality of
connector sections 1010 and a plurality of bridge members 1060
within a plurality of bridge sections 1050. Features of the
expandable device 1000 that are identified with reference numerals
that differ from the reference numerals for the expandable device
100 by a multiple of 100 can have the same aspects as the
corresponding features in the expandable device 100, unless noted
otherwise.
[0119] According to some embodiments, for example as shown in FIGS.
10A and 10B, a helical winding direction of the bridge members 1060
of one bridge section 1050 can be the same as a helical winding
direction of the bridge members 1060 of a different bridge section
1050. According to some embodiments, some or all of the bridge
members 1060 connect to a connector section 1010 at a location that
is not at, or is slightly offset from, a centerline of an apex 1030
of two connector struts 1020.
[0120] According to some embodiments, for example as shown in FIGS.
11A and 11B, an expandable device can comprise some connector
struts that are curved between apices, wherein the connector struts
are parallel to each in a helical winding direction. For example,
at least a portion of each of the connector struts 1120 that are
joined at a given apex 1130 (or at some or all apices 1130 of one,
some or all connector sections 1110) are parallel to each other. In
a given connector section every other connector strut 1120 can have
a curved section near each end, and a straight midsection between
the two curved sections. Such a configuration can shift some of the
strain of device compression or expansion from the apices 1130 to
the curved sections to avoid over-straining or distorting the
apices, and/or to allow a greater degree of device compression or
expansion.
[0121] According to some embodiments, for example as shown in FIGS.
11A and 11B, an expandable device 1100 can comprise a plurality of
connector struts 1120 and apices 1130 within a plurality of
connector sections 1110 and a plurality of bridge members 1160
within a plurality of bridge sections 1150. Features of the
expandable device 1100 that are identified with reference numerals
that differ from the reference numerals for the expandable device
100 by a multiple of 100 can have the same aspects as the
corresponding features in the expandable device 100, unless noted
otherwise.
[0122] According to some embodiments, for example as shown in FIGS.
11A and 11B, a helical winding direction of the bridge members 1160
of one bridge section 1150 can be the same as a helical winding
direction of the bridge members 1160 of a different bridge section
1150. According to some embodiments, some or all of the bridge
members 1160 connect to a connector section 1110 at a location that
is not at, or is slightly offset from, a centerline of an apex 1130
of two connector struts 1120. Optionally, the connector section
1110 located at one or both longitudinal terminal ends of the
device 1100 can comprise a V-strut band such as the connector
section 110 of FIGS. 1A-1B.
[0123] According to some embodiments, for example as shown in FIGS.
12A and 12B, an expandable device can have connector struts that
are coupled together at an apices that have a curve that is
configured to reduce a bend radius at each apex.
[0124] According to some embodiments, for example as shown in FIGS.
12A and 12B, the apices 1230 can have a shape that is configured to
reduce a bend radius at each apex 1230 while preserving the size
and relative orientation of the connector struts 1220. For example,
some or all of the connector struts 1220 can be curved so that as a
pair of struts 1220 approach an apex 1230, the struts 1220 turn
away from each other forming generally parallel terminal portions
that extend to the apex 1230. This allows for a smaller bend radius
at the apex 1230 while preserving the size and angle of the V
formed by the struts 1220. During compression or expansion of the
device 1200, this tends to concentrate bending of each V at the
apex 1230 rather than along the struts 1220 which can cause
undesirable distortion or out-of-plane movement of the struts 1220.
The inside edge of the apex 1230 can be made semicircular. When the
expandable device 1200 is compressed radially, the connector struts
1220 move closer to each other by bending about the apices 1230.
The connector struts 1220 at terminal ends of the expandable device
1200 can have a different shape (e.g., the shape of the connector
struts 120 of the expandable device 100).
[0125] According to some embodiments, for example as shown in FIGS.
12A and 12B, an expandable device 1200 can comprise a plurality of
connector struts 1220 and apices 1230 within a plurality of
connector sections 1210 and a plurality of bridge members 1260
within a plurality of bridge sections 1250. Features of the
expandable device 1200 that are identified with reference numerals
that differ from the reference numerals for the expandable device
100 by a multiple of 100 can have the same aspects as the
corresponding features in the expandable device 100, unless noted
otherwise.
[0126] According to some embodiments, for example as shown in FIGS.
12A and 12B, a helical winding direction of the bridge members 1260
of one bridge section 1250 can be the same as a helical winding
direction of the bridge members 1260 of a different bridge section
1250. According to some embodiments, some or all of the bridge
members 1260 connect to a connector section 1210 at a location that
is not an apex 1230 of two connector struts 1220.
[0127] According to some embodiments, for example as shown in FIGS.
13A and 13B, an expandable device can have some bridge members that
terminate at a pass-through strut 1370 that extends through a
connector section 1310 without contacting or being connected to any
connector struts or apex.
[0128] According to some embodiments, for example as shown in FIGS.
13A and 13B, an expandable device 1300 can comprise a plurality of
connector struts 1320 and apices 1330 within a plurality of
connector sections 1310 and a plurality of bridge members 1360
within a plurality of bridge sections 1350. Features of the
expandable device 1300 that are identified with reference numerals
that differ from the reference numerals for the expandable device
100 by a multiple of 100 can have the same aspects as the
corresponding features in the expandable device 100, unless noted
otherwise.
[0129] According to some embodiments, for example as shown in FIGS.
13A and 13B, a helical winding direction of the bridge members 1360
of one bridge section 1350 can be the same as a helical winding
direction of the bridge members 1360 of a different bridge section
1350. According to some embodiments, some or all of the bridge
members 1360 connect to a connector section 1310 at a location that
is not an apex 1330 of two connector struts 1320.
[0130] According to some embodiments, for example as shown in FIGS.
13A and 13B, some of the bridge members 1360 can terminate at a
pass-through strut 1370 that extends through the connector section
1310 without contacting or being connected to any connector struts
1320 or apex 1330. The pass-through struts 1370 can extend from one
bridge section 1350 to another bridge section 1350 on an opposing
side of the connector section 1310. Only some (e.g., 1/3) of the
bridge members 1360 that connect to a given connector section 1310
connect to a pass-through strut 1370 at that connector section
1310. The remainder of the bridge members 1360 can connect to a
connector strut 1320 or apex 1330 at that connector section 1310.
Each bridge member 1360 that connects to a pass-through strut 1370
on one terminal end of the bridge member 1360 can connect to a
connector strut 1320 and/or an apex 1330 at the opposite terminal
end of the bridge member 1360. Optionally, the connector section
1310 located at one or both longitudinal terminal ends of the
device 1300 can comprise a V-strut band such as the connector
section 110 of FIGS. 1A-1B.
[0131] According to some embodiments, for example as shown in FIGS.
14A and 14B, an expandable device can have an end section at one or
both of its longitudinally terminal ends to provide securement of
the expandable device within a body vessel.
[0132] According to some embodiments, for example as shown in FIGS.
14A and 14B, an expandable device 1400 can comprise a plurality of
connector struts 1420 and apices 1430 within a plurality of
connector sections 1410 and a plurality of bridge members 1460
within a plurality of bridge sections 1450. Features of the
expandable device 1400 that are identified with reference numerals
that differ from the reference numerals for the expandable device
100 by a multiple of 100 can have the same aspects as the
corresponding features in the expandable device 140, unless noted
otherwise.
[0133] According to some embodiments, for example as shown in FIGS.
14A and 14B a helical winding direction of the bridge members 1460
of one bridge section 1450 can be the same as a helical winding
direction of the bridge members 1460 of a different bridge section
1450. According to some embodiments, some or all of the bridge
members 1460 connect to a connector section 1410 at a location that
is not an apex 1430 of two connector struts 1420.
[0134] According to some embodiments, for example as shown in FIGS.
14A and 14B the expandable device 1400 can comprise an end section
1480 at one or both of its longitudinally terminal ends. The end
sections 1480 can be generally stiffer than the bridge sections
1450. Each of the end sections 1480 can comprise end struts 1490.
The end struts 1490 can be interconnected at apices 1495. The end
struts 1490 can form a series of undulations (e.g., sinusoidal or
"S-curves") that extend longitudinally across the some or all of
the end section 1480. The end struts 1490 can be connected to each
other at or near peaks or troughs thereof. The end struts 1490 can
be arranged to form a series of cells that are similar in size and
shape. For example, the cells can be approximately diamond shaped.
The end struts 1490 can be shorter than the bridge members 1460.
For example, the end struts 1490 can be approximately the same
length as the connector struts 1420. The end struts 1490 can
comprise a series of longitudinally adjacent V-strut bands like
that employed as the connector sections 1410. In such a
configuration, every other band can be inverted longitudinally and
the bands connected apex-to-apex as shown in FIG. 14B.
[0135] According to some embodiments, as shown in FIGS. 15A-D, when
an expandable device 1500 is bent to conform to a body vessel with
tortuous curvature, the connector sections 1510 can move closer to
each other on the "inside-curving" side of the expandable device
1500 when the bridge members 1560 collapse longitudinally and move
closer to each other on that side. The thinness and arrangement of
struts provides enhanced longitudinal flexibility and better
arching capability. When deployed in a tortuous body vessel, the
device of the subject technology will readily bend at a bridge
section, thus providing improved wall apposition at a curve. For
example, referring to FIGS. 15A-D, the device 1500 is disposed in a
body vessel with tortuous curvature. At an apex of a curve in the
body vessel, the bridge members 1560 adjacent the apex move toward
each other to facilitate contact with an inner surface of the
vessel, thereby providing improved wall apposition near the apex. A
distance between bridge members 1560 adjacent to the apex of the
curve is less than a distance between bridge members 1560 disposed
away from the apex. By allowing the bridge members 1560 to move
near each other, the bridge members 1560 may better conform to the
shape of the curve. This helps avoid issues that may occur in other
devices, such as tendencies to ovalize, kink, or fish mouth when
placed in a body vessel with tortuous curvature.
[0136] An expandable device may be formed, for example, by laser
cutting a preformed tube or sheet, by interconnecting components
(e.g., by laser welding), by vapor deposition techniques, or
combinations thereof. The expandable device can be formed using
known flexible materials such as nitinol, stainless steel,
cobalt-chromium alloys, Elgiloy, magnesium alloys, tungsten,
tantalum, platinum, or combinations thereof.
[0137] According to some embodiments, an expandable device can be
formed by a photolithography process. A substrate can be provided
with a base for supporting the formation of the expandable device.
The base (e.g., copper) can be used temporarily as a buffer between
the substrate and a primary material used to form the expandable
device. After the base is provided on the substrate, the primary
material is provided thereon, for example by vapor deposition. The
primary material can be provided as a thin film of substantially
uniform thickness. Portions of the primary material can be removed
to form the structure of the expandable device. For example, a
photomask, based on a strut pattern, can be used to selectively
expose portions of the primary material to light and etch the
primary material into the desired shape for the expandable device.
Alternatively or in combination, a chemical agent can be used to
remove the portions of the primary material that are not protected
by a photoresist. The base can then be eroded to separate the
expandable device from the substrate. The expandable device can be
further treated to form a desired shape (e.g., tubular) and have
the desired heat set and/or shape memory properties.
[0138] According to some embodiments, an expandable device can be
formed by a laser cutting process. The expandable device may be
formed by cutting a pattern of struts on a tube or on a flat sheet
and then rolling the flat sheet into a generally tube-like or
coiled shape. The expandable device in a generally tube-like or
coiled shape can be circumferentially continuous or discontinuous.
Where the expandable device is circumferentially discontinuous,
portions of the expandable device can overlap in certain
states.
[0139] As mentioned elsewhere herein, the present disclosure also
includes methods of treating a vascular condition, such as an
aneurysm, with any of the embodiments of the expandable devices
disclosed herein. The expandable device could be deployed across
the neck of an aneurysm and its flow-diverting properties employed
to impede blood flow between the aneurysm and the parent vessel,
cause the blood inside the aneurysm to thrombose, and lead to
healing of the aneurysm.
[0140] In order to implant any of the expandable devices disclosed
herein, the expandable device can be mounted in a delivery system.
Generally, the delivery system can comprise an elongate core member
that supports or contains the expandable device, and both
components can be slidably received in a lumen of a microcatheter
or other elongate sheath for delivery to any region to which the
distal opening of the microcatheter can be advanced. The core
member is employed to advance the expandable device through the
microcatheter and out the distal end of the microcatheter so that
the expandable device is allowed to self-expand into place in the
blood vessel, across an aneurysm or other treatment location.
Accordingly, a vascular treatment apparatus can comprise a delivery
system, such as any of the delivery systems described herein, and
an expandable device, such as any of the expandable devices
described herein, mounted in the delivery system.
[0141] A treatment procedure can begin with obtaining percutaneous
access to the patient's arterial system, typically via a major
blood vessel in a leg or arm. A guidewire can be placed through the
percutaneous access point and advanced to the treatment location,
which can be in an intracranial artery, or any neurovascular
artery, peripheral artery or coronary artery. (As configured for
neurovascular use, any of the expandable devices disclosed herein
can have a diameter of 2-8 mm in the relaxed state or the expanded
state; expandable devices used in the peripheral or coronary
vasculature can have a diameter of 1-20 mm in the relaxed state or
the expanded state.) The microcatheter is then advanced over the
guidewire to the treatment location and situated so that a distal
open end of the guidewire is adjacent to the treatment location.
The guidewire can then be withdrawn from the microcatheter and the
core member, together with the expandable device mounted thereon or
supported thereby, can be advanced through the microcatheter and
out the distal end thereof. The expandable device can then
self-expand into apposition with the inner wall of the blood
vessel. Where an aneurysm is being treated, the expandable device
is placed across the neck of the aneurysm so that a sidewall of the
expandable device separates the interior of the aneurysm from the
lumen of the parent artery. Once the expandable device has been
placed, the core member and microcatheter are removed from the
patient. The expandable device sidewall can now perform a
flow-diverting function on the aneurysm, thrombosing the blood in
the aneurysm and leading to healing of the aneurysm.
[0142] The foregoing description is provided to enable a person
skilled in the art to practice the various configurations described
herein. While the subject technology has been particularly
described with reference to the various figures and configurations,
it should be understood that these are for illustration purposes
only and should not be taken as limiting the scope of the subject
technology.
[0143] There may be many other ways to implement the subject
technology. Various functions and elements described herein may be
partitioned differently from those shown without departing from the
scope of the subject technology. Various modifications to these
configurations will be readily apparent to those skilled in the
art, and generic principles defined herein may be applied to other
configurations. Thus, many changes and modifications may be made to
the subject technology, by one having ordinary skill in the art,
without departing from the scope of the subject technology.
[0144] A phrase such as "an aspect" does not imply that such aspect
is essential to the subject technology or that such aspect applies
to all configurations of the subject technology. A disclosure
relating to an aspect may apply to all configurations, or one or
more configurations. An aspect may provide one or more examples of
the disclosure. A phrase such as "an aspect" may refer to one or
more aspects and vice versa. A phrase such as "an embodiment" does
not imply that such embodiment is essential to the subject
technology or that such embodiment applies to all configurations of
the subject technology. A disclosure relating to an embodiment may
apply to all embodiments, or one or more embodiments. An embodiment
may provide one or more examples of the disclosure. A phrase such
"an embodiment" may refer to one or more embodiments and vice
versa. A phrase such as "a configuration" does not imply that such
configuration is essential to the subject technology or that such
configuration applies to all configurations of the subject
technology. A disclosure relating to a configuration may apply to
all configurations, or one or more configurations. A configuration
may provide one or more examples of the disclosure. A phrase such
as "a configuration" may refer to one or more configurations and
vice versa.
[0145] It is understood that the specific order or hierarchy of
steps in the processes disclosed is an illustration of exemplifying
approaches. Based upon design preferences, it is understood that
the specific order or hierarchy of steps in the processes may be
rearranged. Some of the steps may be performed simultaneously.
Various methods are disclosed presenting elements of the various
steps in a sample order, and are not meant to be limited to the
specific order or hierarchy presented.
[0146] Furthermore, to the extent that the term "include," "have,"
or the like is used herein, such term is intended to be inclusive
in a manner similar to the term "comprise" as "comprise" is
interpreted when employed as a transitional word in a claim.
[0147] A reference to an element in the singular is not intended to
mean "one and only one" unless specifically stated, but rather "one
or more." The term "some" refers to one or more. All structural and
functional equivalents to the elements of the various
configurations described throughout this disclosure that are known
or later come to be known to those of ordinary skill in the art are
expressly incorporated herein by reference and intended to be
encompassed by the subject technology. Moreover, nothing disclosed
herein is intended to be dedicated to the public regardless of
whether such disclosure is explicitly recited in the above
description.
[0148] While certain aspects and embodiments of the subject
technology have been described, these have been presented by way of
example only, and are not intended to limit the scope of the
subject technology. Indeed, the novel methods and systems described
herein may be embodied in a variety of other forms without
departing from the spirit thereof. The numbered clauses and their
equivalents are intended to cover such forms or modifications as
would fall within the scope and spirit of the subject
technology.
* * * * *